1,614 research outputs found

    Chromosome analysis in Saccodon wagneri (Characiformes) and insights into the karyotype evolution of Parodontidae

    Get PDF
    Parodontidae is a relatively small group of Neotropical characiform fishes consisting of three genera (Apareiodon, Parodon, and Saccodon) with 32 valid species. A vast cytogenetic literature is available on Apareiodon and Parodon, but to date, there is no cytogenetic data about Saccodon, a genus that contains only three species with a trans-Andean distribution. In the present study the karyotype of S. wagneri was described, based on both conventional (Giemsa staining, Ag- NOR, C-bands) and molecular (repetitive DNA mapping by fluorescent in situ hybridization) methods. A diploid chromosome number of 2n = 54 was observed in both sexes, and the presence of heteromorphic sex chromosomes of the ZZ/ ZW type was detected. The W chromosome has a terminal heterochromatin band that occupies approximately half of the long arm, being this band approximately half the size of the Z chromosome. The FISH assay showed a synteny of the 18S-rDNA and 5S-rDNA genes in the chromosome pair 14, and the absence of interstitial telomeric sites. Our data reinforce the hypothesis of a conservative karyotype structure in Parodontidae and suggest an ancient origin of the sex chromosomes in the fishes of this family

    Adhesion Strength of Aluminum on Metallized Plastic Films Used in Flexible Packages - Development and Validation of a Test Procedure

    Get PDF
    OPP and OPET metallized films are widely used as substrates in multi layer packages, since they bring together good mechanical properties and barrier to gases and water vapor, which are damaged with delamination of the film layers, together with the visual appearance and package integrity. One of the main factors that affect the package delamination is the adhesion strength of aluminum layer to the polymeric substrate, a parameter for which there is no standard procedure to quantify. The aim of this work was to establish and validate a procedure to determine the adhesion strength of the aluminum to the polymer. This test procedure was carried out using experimental design with fixed and variables parameters with two levels for each variable. The test procedure was stable, robust and replicable. It consisted basically of the heat sealing of a plastic film to the metallized sample surface, under specific temperature/time/pressure conditions and the measuring of adhesion strength of metallization in a universal test machine running at specific angle and speed.21323323

    Antibacterial evaluation of Anacardium occidentale (Linn) (Anacardiaceae) in semiarid Brazil

    Get PDF
    Microorganisms that cause losses are proving to be resistant to most known antibiotics, thereby encouraging the search for naturally occurring antibiotics. This study aimed to perform a phytochemical and bacterial study of ethanolic extracts of leaves and barks of Anacardium occidentale L. The samples were submitted for extraction using ethyl alcohol; the crude extract was used to perform phytochemical evaluation based on the identification of chemical constituents and to evaluate the antibacterial activity. The results of prospective chemical indicate the presence of tannins, phenols, alkaloids and catechins in the leaves and stem bark and compounds belonging to classes of flavonoids were found only in the leaves. Tests using the agar diffusion method for later determination of minimum inhibitory concentration (MIC) revealed that both parts of the plant have antibacterial activity, but the shell showed the largest zones of inhibition in most of the concentrations and strains. The MIC ranged from 512 to ≥ 1024 μg/ml, for the two parts of this species. The results indicate the need for further studies because this plant demonstrated considerable antibacterial therapeutic potential.Keywords: Antibacterial activity, phytochemicals, bacteria, minimum inhibitory concentrationAfrican Journal of Biotechnology Vol. 12(30), pp. 4836-484

    Challenges in public perception: highlights from the United Kingdom-Brazil Dementia Workshop

    Get PDF
    In July 2019, Belo Horizonte hosted an international workshop for 27 junior researchers, whose participants were from Brazil and the United Kingdom. This three-day meeting organized by the Universidade Federal de Minas Gerais and the University of East Anglia addressed challenges in cognitive impairment and dementia, with particular interest in public perceptions, diagnosis and care management. The purpose of this report is to highlight the outcomes of the above-mentioned workshop regarding the topic of public perceptions (part I). Discussions focused on differences and similarities between countries, as well as on identifying main issues that required collaborative and creative solutions. After these group discussions, four core themes emerged: I) cognitive impairment; II) dementia - beyond Alzheimer's disease; III) prevention; and IV) stigma. National and international initiatives to deal with public misperceptions about cognitive impairment and dementia were discussed

    Maternal morbidity and near miss associated with maternal age: the innovative approach of the 2006 Brazilian demographic health survey

    Get PDF
    OBJECTIVE: To study the prevalence of potentially life-threatening maternal conditions and near miss in Brazil according to maternal age. METHODS: A secondary analysis of the 2006 Brazilian demographic health survey database using a validated questionnaire to evaluate maternal morbidity with a focus on age extremes. The study included 5,025 women with at least 1 live birth in the 5-year reference period preceding their interviews. Three age range periods were used: 15-19 years (younger age), 20-34 years (control), and 35-49 years (advanced maternal age). According to a pragmatic definition, any woman reporting eclampsia, hysterectomy, blood transfusion, or admission to the intensive care unit during her pregnancy/childbirth was considered a near-miss case. The associations between age and severe maternal morbidity were further assessed. RESULTS: For the 6,833 reported pregnancies, 73.7% of the women were 20-34 years old, 17.9% were of advanced maternal age, and only 8.4% were of younger age. More than 22% of the women had at least one of the complications appraised, and blood transfusion, which was more prevalent among the controls, was the only variable with a significant difference among the age groups. The overall rate of maternal near miss was 21.1 per 1000 live births. There was a trend of higher maternal near miss with increasing age. The only significant risk factor identified for maternal near miss was a lower literacy level among older women. CONCLUSIONS: There is a trend towards worse results with increasing age. The investigation of the determinants of maternal near miss at the community level using an innovative approach through a demographic health survey is an example suggested for under-resourced settings

    Modeling the quantum evolution of the universe through classical matter

    Full text link
    It is well known that the canonical quantization of the Friedmann-Lema\^itre-Robertson-Walker (FLRW) filled with a perfect fluid leads to nonsingular universes which, for later times, behave as their classical counterpart. This means that the expectation value of the scale factor (t)(t) never vanishes and, as tt\to\infty, we recover the classical expression for the scale factor. In this paper, we show that such universes can be reproduced by classical cosmology given that the universe is filled with an exotic matter. In the case of a perfect fluid, we find an implicit equation of state (EoS). We then show that this single fluid with an implict EoS is equivalent to two non-interacting fluids, one of them representing stiff matter with negative energy density. In the case of two non-interacting scalar fields, one of them of the phantom type, we find their potential energy. In both cases we find that quantum mechanics changes completely the configuration of matter for small values of time, by adding a fluid or a scalar field with negative energy density. As time passes, the density of negative energy decreases and we recover the ordinary content of the classical universe. The more the initial wave function of the universe is concentrated around the classical big bang singularity, the more it is necessary to add negative energy, since this type of energy will be responsible for the removal of the classical singularity.Comment: updated version as accepted by Gen. Relativ. Gravi

    Effect of maternal Schistosoma mansoni infection and praziquantel treatment during pregnancy on Schistosoma mansoni infection and immune responsiveness among offspring at age five years.

    Get PDF
    INTRODUCTION: Offspring of Schistosoma mansoni-infected women in schistosomiasis-endemic areas may be sensitised in-utero. This may influence their immune responsiveness to schistosome infection and schistosomiasis-associated morbidity. Effects of praziquantel treatment of S. mansoni during pregnancy on risk of S. mansoni infection among offspring, and on their immune responsiveness when they become exposed to S. mansoni, are unknown. Here we examined effects of praziquantel treatment of S. mansoni during pregnancy on prevalence of S. mansoni and immune responsiveness among offspring at age five years. METHODS: In a trial in Uganda (ISRCTN32849447, http://www.controlled-trials.com/ISRCTN32849447/elliott), offspring of women treated with praziquantel or placebo during pregnancy were examined for S. mansoni infection and for cytokine and antibody responses to SWA and SEA, as well as for T cell expression of FoxP3, at age five years. RESULTS: Of the 1343 children examined, 32 (2.4%) had S. mansoni infection at age five years based on a single stool sample. Infection prevalence did not differ between children of treated or untreated mothers. Cytokine (IFNγ, IL-5, IL-10 and IL-13) and antibody (IgG1, Ig4 and IgE) responses to SWA and SEA, and FoxP3 expression, were higher among infected than uninfected children. Praziquantel treatment of S. mansoni during pregnancy had no effect on immune responses, with the exception of IL-10 responses to SWA, which was higher in offspring of women that received praziquantel during pregnancy than those who did not. CONCLUSION: We found no evidence that maternal S. mansoni infection and its treatment during pregnancy influence prevalence and intensity of S. mansoni infection or effector immune response to S. mansoni infection among offspring at age five years, but the observed effects on IL-10 responses to SWA suggest that maternal S. mansoni and its treatment during pregnancy may affect immunoregulatory responsiveness in childhood schistosomiasis. This might have implications for pathogenesis of the disease
    corecore